<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<h1 onclick="this.innerHTML='hello!!'">点击此处</h1>
		<br>
		<h1 onclick="changer(this)">aaa</h1>
		<br>
		<button id="mybtn"> try</button>
		<br>
		<div id="demo"></div>
	</body>
</html>
<script>
	function changer(id){
		id.innerHTML="HAHAHAHAH"
	}
	document.getElementById("mybtn").onclick=showMessage;
	function showMessage(){
		document.getElementById("demo").innerHTML=Date();
		
	}
</script>